diff --git a/minui/graphics_overlay.cpp b/minui/graphics_overlay.cpp
index b7e62d9..5988d70 100644
--- a/minui/graphics_overlay.cpp
+++ b/minui/graphics_overlay.cpp
@@ -448,12 +448,10 @@
     if (double_buffered) {
 #if defined(RECOVERY_BGRA)
         // In case of BGRA, do some byte swapping
-        unsigned int idx;
-        unsigned char tmp;
         unsigned char* ucfb_vaddr = (unsigned char*)gr_draw->data;
-        for (idx = 0 ; idx < (gr_draw->height * gr_draw->row_bytes);
+        for (int idx = 0 ; idx < (gr_draw->height * gr_draw->row_bytes);
                 idx += 4) {
-            tmp = ucfb_vaddr[idx];
+            unsigned char tmp = ucfb_vaddr[idx];
             ucfb_vaddr[idx    ] = ucfb_vaddr[idx + 2];
             ucfb_vaddr[idx + 2] = tmp;
         }